This invention relates to a cryptographic system for enciphering and deciphering a digital signal conveying messages in data transmission networks. It is often necessary to protect stored and transmitted data from unauthorized parties or eavesdroppers. Cryptography offers the protection necessary for data privacy. However, as the required amount of privacy increases, the processing time for enciphering and deciphering a plaintext lengthens due to an increased complexity of the cryptography. It is desirable to have a simpler and faster cryptographic process and to provide a higher secrecy of data.